The claims on your label and in your marketing are where a supplement brand is won or lost, legally and commercially. Say too little and the product feels flat. Say too much and you've turned a supplement into an unapproved drug in the eyes of the FDA and made a claim the FTC can call misleading. Most founders don't cross that line on purpose. They cross it because no one told them where it is. So let's draw it clearly.

Two kinds of claims, one bright line

U.S. regulators sort supplement claims into two buckets, and the entire game is knowing which bucket you're in.

Structure/function claims: allowed

A structure/function claim describes how an ingredient is designed to support a normal structure or function of the body. These are the claims supplements are permitted to make. They're about supporting how a healthy body already works, not about fixing something that's broken.

Disease claims: not allowed

A disease claim states or implies that a product diagnoses, treats, cures, mitigates, or prevents a disease. The moment your language does that, your product is legally a drug, and drugs require FDA approval your supplement doesn't have. This is the single most common way good founders get a warning letter.

Structure/function language supports how a healthy body works. Disease language promises to fix what's wrong. One is a supplement. The other is an unapproved drug.

Worth knowing: implication counts. You can cross into a disease claim without ever naming a disease: through an ingredient's reputation, an image, a customer testimonial, or the name of the product itself. Regulators read the whole context, not just the sentence.

The disclaimer you're required to carry

If you make a structure/function claim, the law requires a disclaimer on the label: the familiar statement that the claim has not been evaluated by the FDA and that the product is not intended to diagnose, treat, cure, or prevent any disease. You're also expected to notify the FDA of the claim within 30 days of first marketing the product. That disclaimer isn't fine print to hide; it's the permission slip that lets structure/function claims exist at all. (We cover why none of this is “FDA approval” in Do You Need FDA Approval to Launch a Supplement?)

The FTC's standard: truthful and substantiated

The FDA governs your label. The FTC governs your advertising (your website, ads, emails, and social posts) and applies a second test on top of everything above: every claim must be truthful, not misleading, and supported by competent and reliable evidence before you make it.

Two things founders underestimate here. First, the substantiation has to exist before you publish the claim, not after someone challenges it. Second, the FTC looks at the net impression a reasonable customer takes away, so a technically-true sentence framed to imply a dramatic outcome can still be deemed deceptive. Honesty and evidence aren't just ethics; they're the standard.

Safe wording vs. wording to avoid

Concrete examples make the line easier to see. These are illustrative, not a substitute for a professional review of your specific product.

Wording that tends to be safe

  • “Designed to support healthy sleep patterns”
  • “Formulated to support a normal, healthy inflammatory response”
  • “Supports focus and mental sharpness as part of a healthy lifestyle”
  • “Helps maintain bone health”
  • “Supports the body's natural energy production”

Wording to avoid

  • “Cures insomnia”: names and treats a disease
  • “Treats arthritis” or “reduces inflammation from arthritis”: disease treatment
  • “Prevents Alzheimer's”: disease prevention
  • “Reverses aging” or “guaranteed results”: unsupportable and overpromising
  • “FDA-approved supplement”: no such thing, and misleading on its face

Notice the pattern: the safe versions use “designed to,” “supports,” “helps maintain,” and stay anchored to normal, healthy function. The risky versions promise to fix a condition or guarantee an outcome. When in doubt, ask whether you're describing support for a healthy body or a fix for a sick one.

A working rule of thumb: if a claim would be more impressive to someone who is sick than to someone who is healthy, it's probably drifting toward a disease claim. Keep the language about supporting normal function, use “designed to” and “built to” rather than “will,” and make sure you can back up every word before you publish it.

Marketing responsibly is a strategy, not a constraint

Founders sometimes treat compliant claims as a ceiling on their marketing. In practice, disciplined claims are a competitive advantage. They keep your brand off the FDA and FTC's radar, they build trust with customers who are tired of miracle promises, and they force you to compete on the things that actually build equity: formulation quality, brand, and a genuine understanding of your customer.

The best time to set your claims guardrails is during development, when you can still shape the formula and the story together. That's how we approach supplement product development: a science-informed formula and a responsible claims strategy built side by side, so your marketing is both compelling and defensible from launch. If you're still weighing how to build the product itself, Private Label vs. Custom Formulation is a useful companion read.

This article is educational and is not legal or regulatory advice. Product claims, labels, and advertising should be reviewed by qualified regulatory and legal professionals before launch.